NEENAH - Firefighters responded to a fire at Shattuck Middle School in Neenah on Thursday evening.

They were dispatched about 5 p.m. to the school at 600 Elm St. for a report of the roof on fire, Neenah-Menasha Fire Rescue Shift Commander Dan Schultz told a USA TODAY NETWORK-Wisconsin reporter on scene.

They were able to knock the fire down within about 15 minutes, he said. Nobody was inside the building when the fire started and no one was hurt.

The school district was in the process of replacing the roof before the fire started, Neenah Joint School District Facilities Director Adam Krieger said.

Assistant Chief Vernon Green said Friday that part of a mop used for applying hot tar on the roof likely caught fire, causing the small fire. Damage was estimated to be about $1,500.

The firefighters were in the parking lot by the main entrance around 5:20 p.m. and smoke was visible from the building, according to a reporter on scene.

The Neenah Joint School District said in a tweet that the fire was confined to the roof.